Some light emitting devices use light emitting diodes (LEDs) or similar devices as their light sources. These light sources are very efficient and are being used in a variety of different applications. LEDs are sensitive to heat and do not operate well in hot environments. Many applications, however, require bright light, which requires that the LEDs draw a lot of current and produce a lot of extra heat. One method of cooling LEDs is to locate them on a heat conducting surface such as a ceramic substrate.
One problem with ceramic substrates is that they are difficult to cut. Accordingly, it is difficult to cut a recess deep enough to form a reflector cup for an LED in a ceramic substrate. Thus, LEDs mounted on ceramic substrates are typically expensive or lack adequate reflector cups.